If a drain valve is desired, remove the handle from the valve stem to gain clearance for valve body rotation. Add Loctite 242 (furnished) to the threads and rotate valve body until secure, with the valve stem (for handle) on the left side. Re-install handle to valve stem. Adjust the cabinet on bench to provide a 1-1/2" (38mm) overhang and seal the interface of the bench and cabinet, using RTV sealant as above.